Abstract As of 4/30/2020, the Coronavirus Disease 2019 (COVID-19) has infected more than one million people and caused 60,057 deaths in the United States. Neither the clinical symptoms nor the radiological features of COVID- 19 are specific to the disease, resulting in significant challenges to the screening and early diagnosis of this highly infectious disease. The current gold standard method for COVID-19 diagnosis, the reverse transcriptase polymerase chain reaction (RT-PCR) test, has a relatively long turnaround time. Chest x-ray radiography (CXR) has been widely used in the United States for COVID-19 assessment since the first case reported in the US. However, the major challenge with the use of CXR is its low sensitivity and specificity to COVID-19, which is largely attributed to the lack of x-ray absorption contrast sensitivity to mild alveolar damages in the early phases of COVID-19. In this Emergency Competitive Revision, we offer a quick response to the imperative clinical need to improve the diagnostic accuracy of CXR to COVID-19 by leveraging the multi-contrast x-ray imaging technology developed in our ongoing R01 project (EB020521). In particular, the x-ray dark field contrast mechanism is orders of magnitude more sensitive to partial fillings or collapses of alveoli and thus is expected to offer a significant boost to CXR?s sensitivity to alveolar damage. We will quickly construct a multi-contrast chest x-ray radiography (MC-CXR) system, characterize its physical performance, evaluate its radiation safety, and optimize its scan protocols. Finally, we will conduct a pilot human subject study to collect initial evidence for its clinical value in diagnosing COVID-19. Considering the high likelihood for a second wave of COVID-19, the availability of the proposed MC-CXR system can facilitate the hospital systems to cope with additional rounds of patient surge by providing rapid ?entrance? assessment of COVID-19.